xref: /netbsd/usr.bin/find/find.1 (revision 6550d01e)
1.\"	$NetBSD: find.1,v 1.70 2010/09/09 11:42:13 wiz Exp $
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33.\"	from: @(#)find.1	8.7 (Berkeley) 5/9/95
34.\"
35.Dd November 6, 2009
36.Dt FIND 1
37.Os
38.Sh NAME
39.Nm find
40.Nd walk a file hierarchy
41.Sh SYNOPSIS
42.Nm
43.Op Fl H | Fl L | Fl P
44.Op Fl dEhsXx
45.Ar file
46.Op Ar file ...
47.Op Ar expression
48.Nm
49.Op Fl H | Fl L | Fl P
50.Op Fl dEhsXx
51.Fl f Ar file
52.Op Ar file ...
53.Op Ar expression
54.Sh DESCRIPTION
55.Nm
56recursively descends the directory tree for each
57.Ar file
58listed, evaluating an
59.Ar expression
60(composed of the
61.Dq primaries
62and
63.Dq operands
64listed below) in terms
65of each file in the tree.
66.Pp
67The options are as follows:
68.Pp
69.Bl -tag -width Ds
70.It Fl H
71The
72.Fl H
73option causes the file information and file type (see
74.Xr stat 2 ) ,
75returned for each symbolic link encountered on the command line to be
76those of the file referenced by the link, not the link itself.
77If the referenced file does not exist, the file information and type will
78be for the link itself.
79File information of all symbolic links not on the command line is that
80of the link itself.
81.It Fl L
82The
83.Fl L
84option causes the file information and file type (see
85.Xr stat 2 )
86returned for each symbolic link to be those of the file referenced by the
87link, not the link itself.
88If the referenced file does not exist, the file information and type will
89be for the link itself.
90.It Fl P
91The
92.Fl P
93option causes the file information and file type (see
94.Xr stat 2 )
95returned for each symbolic link to be those of the link itself.
96.It Fl d
97The
98.Fl d
99option causes
100.Nm
101to perform a depth-first traversal, i.e., directories
102are visited in post-order and all entries in a directory will be acted
103on before the directory itself.
104By default,
105.Nm
106visits directories in pre-order, i.e., before their contents.
107Note, the default is
108.Ar not
109a breadth-first traversal.
110.It Fl E
111The
112.Fl E
113option causes
114.Ar regexp
115arguments to primaries to be interpreted as extended regular
116expressions (see
117.Xr re_format 7 ) .
118.It Fl f
119The
120.Fl f
121option specifies a file hierarchy for
122.Nm
123to traverse.
124File hierarchies may also be specified as the operands immediately
125following the options.
126.It Fl h
127The
128.Fl h
129option causes the file information and file type (see
130.Xr stat  2  ) ,
131returned for each symbolic link to be those of the file referenced by the
132link, not the link itself.
133If the referenced file does not exist, the file information and type will
134be for the link itself.
135.It Fl s
136The
137.Fl s
138option causes the entries of each directory to be sorted in
139lexicographical order.
140Note that the sorting is done only inside of each directory;
141files in different directories are not sorted.
142Therefore,
143.Sq Li a/b
144appears before
145.Sq Li a.b ,
146which is different from
147.Dq Li "find ... \&| sort"
148order.
149.It Fl X
150The
151.Fl X
152option is a modification to permit
153.Nm
154to be safely used in conjunction with
155.Xr xargs 1 .
156If a file name contains any of the delimiting characters used by
157.Nm xargs ,
158a diagnostic message is displayed on standard error, and the file
159is skipped.
160The delimiting characters include single
161.Pq Dq \&'
162and double
163.Pq Dq \&"
164quotes, backslash
165.Pq Dq \e ,
166space, tab and newline characters.
167Alternatively, the
168.Ic -print0
169or
170.Ic -printx
171primaries can be used to format the output in a way that
172.Nm xargs
173can accept.
174.It Fl x
175The
176.Fl x
177option restricts the search to the file system containing the
178directory specified.
179Does not list mount points to other file systems.
180.El
181.Sh PRIMARIES
182.Bl -tag -width Ds -compact
183.It Ic -amin Ar n
184True if the difference between the file last access time and the time
185.Nm
186was started, rounded up to the next full minute, is
187.Ar n
188minutes.
189.Pp
190.It Ic -anewer Ar file
191True if the current file has a more recent last access time than
192.Ar file  .
193.Pp
194.It Ic -atime Ar n
195True if the difference between the file last access time and the time
196.Nm
197was started, rounded up to the next full 24-hour period, is
198.Ar n
19924-hour periods.
200.Pp
201.It Ic -cmin Ar n
202True if the difference between the time of last change of file status
203information and the time
204.Nm
205was started, rounded up to the next full minute, is
206.Ar n
207minutes.
208.Pp
209.It Ic -cnewer Ar file
210True if the current file has a more recent last change time than
211.Ar file  .
212.Pp
213.It Ic -ctime Ar n
214True if the difference between the time of last change of file status
215information and the time
216.Nm
217was started, rounded up to the next full 24-hour period, is
218.Ar n
21924-hour periods.
220.Pp
221.It Ic -delete
222Delete found files, symbolic links and directories.
223Always returns True.
224This executes from the current working directory as
225.Nm
226recurses down the tree.
227To avoid deleting unexpected files, it will ignore any filenames that
228.Xr fts 3
229returns that contain a
230.Dq /
231.Xr ( fts 3
232should not return such pathnames).
233Depth-first traversal processing is implied by this option.
234This can also be invoked as
235.Ic -rm .
236.Pp
237.It Ic -empty
238True if the current file or directory is empty.
239.Pp
240.It Ic -exec Ar utility Oo argument ... Oc No ;
241.It Ic -exec Ar utility Oo argument ... Oc No {} +
242Execute the specified
243.Ar utility
244with the specified arguments.
245The list of arguments is terminated by
246.Dq Li \&;
247or
248.Dq Li \&+ .
249.Ar utility
250will be executed from the directory from which
251.Nm
252was executed.
253.Pp
254If terminated by a semicolon
255.Pq Dq \&; ,
256the
257.Ar utility
258is invoked once per path.
259If the string
260.Dq {}
261appears anywhere in the utility name or the arguments,
262it is replaced by the pathname of the current file.
263.Pp
264If terminated by a plus sign
265.Pq Dq \&+ ,
266the pathnames for which the
267primary is evaluated are aggregated into sets, and
268.Ar utility
269will be invoked once per set, similar to
270.Xr xargs 1 .
271If any invocation exits with non-zero exit status, then
272.Nm
273will eventually do so as well, but this does not cause
274.Nm
275to exit early.
276The string
277.Dq {}
278must appear, and must appear last.
279Each set is limited to no more than 5,000 pathnames,
280and is also limited such that the invocation of
281.Ar utility
282does not exceed
283.Dv ARG_MAX .
284.Pp
285.It Ic -execdir Ar utility Oo argument ... Oc No ;
286The
287.Ic -execdir
288primary is similar to the semicolon-terminated
289.Pq Dq \&;
290variant of the
291.Ic -exec
292primary, with the exception that
293.Ar utility
294will be executed from the directory that holds
295the current file.
296The filename substituted for the string
297.Dq {}
298is not qualified.
299Set aggregation
300.Pq Do \&+ Dc termination
301is not supported.
302.Pp
303.It Ic -exit Op Ar n
304This primary causes
305.Nm
306to stop traversing the file system and exit immediately if a
307previous condition was met.
308If no value is specified, the exit value will be 0, else
309.Ar n .
310Note that other primaries will be evaluated and acted upon before exiting.
311.Pp
312.It Ic -false
313This primary always evaluates to false.
314This can be used following a primary that caused the
315expression to be true to make the expression to be false.
316This can be useful after using a
317.Ic -fprint
318primary so it can continue to the next expression (using an
319.Cm -or
320operator, for example).
321.Pp
322.It Ic -flags Oo Fl Oc Ns Ar flags
323If
324.Ar flags
325are preceded by a dash
326.Pq Dq - ,
327this primary evaluates to true
328if at least all of the bits in
329.Ar flags
330are set in the file's flags bits.
331If
332.Ar flags
333are not preceded by a dash, this primary evaluates to true if
334the bits in
335.Ar flags
336exactly match the file's flags bits.
337If
338.Ar flags
339is
340.Dq none ,
341files with no flags bits set are matched.
342(See
343.Xr chflags 1
344for more information about file flags.)
345.Pp
346.It Ic -follow
347Follow symbolic links.
348.Pp
349.It Ic -fprint Ar filename
350This primary always evaluates to true.
351This creates
352.Ar filename
353or overwrites the file if it already exists.
354The file is created at startup.
355It writes the pathname of the current file to this file, followed
356by a newline character.
357The file will be empty if no files are matched.
358.Pp
359.It Ic -fstype Ar type
360True if the file is contained in a file system of type
361.Ar type .
362The
363.Xr sysctl 8
364command can be used to find out the types of file systems
365that are available on the system:
366.Bd -literal -offset indent
367sysctl vfs.generic.fstypes
368.Ed
369.Pp
370In addition, there are two pseudo-types,
371.Dq local
372and
373.Dq rdonly .
374The former matches any file system physically mounted on the system where
375the
376.Nm
377is being executed, and the latter matches any file system which is
378mounted read-only.
379.Pp
380.It Ic -group Ar gname
381True if the file belongs to the group
382.Ar gname  .
383If
384.Ar gname
385is numeric and there is no such group name, then
386.Ar gname
387is treated as a group id.
388.Pp
389.It Ic -iname Ar pattern
390True if the last component of the pathname being examined
391matches
392.Ar pattern .
393Case insensitive.
394.Pp
395.It Ic -inum Ar n
396True if the file has inode number
397.Ar n  .
398.Pp
399.It Ic -iregex Ar regexp
400True if the path name of the current file matches the case-insensitive
401basic regular expression
402.Pq see Xr re_format 7
403.Ar regexp .
404This is a match on the whole path, not a search for the regular expression
405within the path.
406.Pp
407.It Ic -links Ar n
408True if the file has
409.Ar n
410links.
411.Pp
412.It Ic -rm
413This is an alias for
414.Ic -delete .
415.Pp
416.It Ic -ls
417This primary always evaluates to true.
418The following information for the current file is written to standard output:
419its inode number, size in 512-byte blocks, file permissions, number of hard
420links, owner, group, size in bytes, last modification time, and pathname.
421If the file is a block or character special file, the major and minor numbers
422will be displayed instead of the size in bytes.
423If the file is a symbolic link, the pathname of the linked-to file will be
424displayed preceded by
425.Dq -\*[Gt] .
426The format is identical to that produced by
427.Dq ls -dgils .
428.Pp
429.It Ic -maxdepth Ar n
430True if the current search depth is less than or equal to what is specified in
431.Ar n .
432.Pp
433.It Ic -mindepth Ar n
434True if the current search depth is at least what is specified in
435.Ar n .
436.Pp
437.It Ic -mmin Ar n
438True if the difference between the file last modification time and the time
439.Nm
440was started, rounded up to the next full minute, is
441.Ar n
442minutes.
443.Pp
444.It Ic -mtime Ar n
445True if the difference between the file last modification time and the time
446.Nm
447was started, rounded up to the next full 24-hour period, is
448.Ar n
44924-hour periods.
450.Pp
451.It Ic -ok Ar utility Oo argument ... Oc No ;
452The
453.Ic -ok
454primary is similar to the semicolon-terminated
455.Pq Dq \&;
456variant of the
457.Ic -exec
458primary, with the exception that
459.Nm
460requests user affirmation for the execution of the utility by printing
461a message to the terminal and reading a response.
462If the response is other than
463.Dq y ,
464the command is not executed and the
465.Ar -ok
466primary evaluates to false.
467Set aggregation
468.Pq Do \&+ Dc termination
469is not supported.
470.Pp
471.It Ic -name Ar pattern
472True if the last component of the pathname being examined matches
473.Ar pattern  .
474Special shell pattern matching characters
475.Po
476.Dq \&[ ,
477.Dq \&] ,
478.Dq \&* ,
479.Dq \&?
480.Pc
481may be used as part of
482.Ar pattern  .
483These characters may be matched explicitly by escaping them with a
484backslash
485.Pq Dq \e .
486.Pp
487.It Ic -newer Ar file
488True if the current file has a more recent last modification time than
489.Ar file  .
490.Pp
491.It Ic -nouser
492True if the file belongs to an unknown user.
493.Pp
494.It Ic -nogroup
495True if the file belongs to an unknown group.
496.Pp
497.It Ic -path Ar pattern
498True if the pathname being examined matches
499.Ar pattern  .
500Special shell pattern matching characters
501.Po
502.Dq \&[ ,
503.Dq \&] ,
504.Dq \&* ,
505and
506.Dq \&?
507.Pc
508may be used as part of
509.Ar pattern  .
510These characters may be matched explicitly by escaping them with a
511backslash
512.Pq Dq \e .
513Slashes
514.Pq Dq /
515are treated as normal characters and do not have to be
516matched explicitly.
517.Pp
518.It Ic -perm Oo Fl Oc Ns Ar mode
519The
520.Ar mode
521may be either symbolic (see
522.Xr chmod  1  )
523or an octal number.
524If the mode is symbolic, a starting value of zero is assumed and the
525mode sets or clears permissions without regard to the process' file mode
526creation mask.
527If the mode is octal, only bits 07777
528.Pf ( Dv S_ISUID
529|
530.Dv S_ISGID
531|
532.Dv S_ISTXT
533|
534.Dv S_IRWXU
535|
536.Dv S_IRWXG
537|
538.Dv S_IRWXO )
539of the file's mode bits participate
540in the comparison.
541If the mode is preceded by a dash
542.Pq Dq - ,
543this primary evaluates to true
544if at least all of the bits in the mode are set in the file's mode bits.
545If the mode is not preceded by a dash, this primary evaluates to true if
546the bits in the mode exactly match the file's mode bits.
547Note, the first character of a symbolic mode may not be a dash
548.Pq Dq - .
549.Pp
550.It Ic -print
551This primary always evaluates to true.
552It prints the pathname of the current file to standard output, followed
553by a newline character.
554If none of
555.Ic -exec ,
556.Ic -exit ,
557.Ic -fprint ,
558.Ic -ls ,
559.Ic -ok ,
560.Ic -print0 ,
561nor
562.Ic -printx
563is specified, the given expression shall be effectively replaced by
564.Cm \&( Ns Ar given\& expression Ns Cm \&)
565.Ic -print .
566.Pp
567.It Ic -print0
568This primary always evaluates to true.
569It prints the pathname of the current file to standard output, followed
570by a null character.
571.Pp
572.It Ic -printx
573This primary always evaluates to true.
574It prints the pathname of the current file to standard output,
575with each space, tab, newline, backslash, dollar sign, and single,
576double, or back quotation mark prefixed by a backslash, so the output of
577.Nm find
578can safely be used as input to
579.Nm xargs .
580.Pp
581.It Ic -prune
582This primary always evaluates to true.
583It causes
584.Nm
585to not descend into the current file.
586Note, the
587.Ic -prune
588primary has no effect if the
589.Fl d
590option was specified.
591.Pp
592.It Ic -regex Ar regexp
593True if the path name of the current file matches the case-sensitive
594basic regular expression
595.Pq see Xr re_format 7
596.Ar regexp .
597This is a match on the whole path, not a search for the regular expression
598within the path.
599.Pp
600.It Ic -size Ar n Ns Op Cm c
601True if the file's size, rounded up, in 512-byte blocks is
602.Ar n  .
603If
604.Ar n
605is followed by a
606.Dq c ,
607then the primary is true if the file's size is
608.Ar n
609bytes.
610.Pp
611.It Ic -type Ar t
612True if the file is of the specified type.
613Possible file types are as follows:
614.Pp
615.Bl -tag -width flag -offset indent -compact
616.It Cm b
617block special
618.It Cm c
619character special
620.It Cm d
621directory
622.It Cm f
623regular file
624.It Cm l
625symbolic link
626.It Cm p
627FIFO
628.It Cm s
629socket
630.It Cm W
631whiteout
632.It Cm w
633whiteout
634.El
635.Pp
636.It Ic -user Ar uname
637True if the file belongs to the user
638.Ar uname  .
639If
640.Ar uname
641is numeric and there is no such user name, then
642.Ar uname
643is treated as a user id (and considered a numeric argument).
644.Pp
645.It Ic -xdev
646This primary always evaluates to true.
647It causes find not to descend past directories that have a different
648device ID (st_dev, see
649.Xr stat 2
650S5.6.2 [POSIX.1]).
651.El
652.Pp
653All primaries which take a numeric argument allow the number to be
654preceded by a plus sign
655.Pq Dq +
656or a minus sign
657.Pq Dq \- .
658A preceding plus sign means
659.Dq more than n ,
660a preceding minus sign means
661.Dq less than n ,
662and neither means
663.Dq exactly n .
664.Sh OPERATORS
665The primaries may be combined using the following operators.
666The operators are listed in order of decreasing precedence.
667.Bl -tag -width (expression)
668.It Cm \&( Ar expression Cm \&)
669This evaluates to true if the parenthesized expression evaluates to
670true.
671.Pp
672.It Cm \&! Ar expression
673This is the unary
674.Tn NOT
675operator.
676It evaluates to true if the expression is false.
677.Pp
678.It Ar expression Cm -and Ar expression
679.It Ar expression expression
680The
681.Cm -and
682operator is the logical
683.Tn AND
684operator.
685As it is implied by the juxtaposition of two expressions it does not
686have to be specified.
687The expression evaluates to true if both expressions are true.
688The second expression is not evaluated if the first expression is false.
689.Pp
690.It Ar expression Cm -or Ar expression
691The
692.Cm -or
693operator is the logical
694.Tn OR
695operator.
696The expression evaluates to true if either the first or the second expression
697is true.
698The second expression is not evaluated if the first expression is true.
699.El
700.Pp
701All operands and primaries must be separate arguments to
702.Nm  .
703Primaries which themselves take arguments expect each argument
704to be a separate argument to
705.Nm  .
706.Sh EXIT STATUS
707The
708.Nm
709utility normally exits 0 on success, and exits with 1 under certain
710internal error conditions.
711If any invocations of
712.Dq Ic -exec Ar ... No +
713primaries return non-zero exit-status, then
714.Nm
715will do so as well.
716.Sh EXAMPLES
717The following examples are shown as given to the shell:
718.Bl -tag -width findx
719.It Li "find  /  \e!  -name  \*q*.c\*q  -print"
720Print out a list of all the files whose names do not end in
721.Dq \&.c .
722.It Li "find  /  -newer  ttt  -user  wnj  -print"
723Print out a list of all the files owned by user
724.Dq wnj
725that are newer than the file
726.Dq ttt .
727.It Li "find  /  \e!  \e(  -newer  ttt  -user  wnj  \e)  -print"
728Print out a list of all the files which are not both newer than
729.Dq ttt
730and owned by
731.Dq wnj .
732.It Li "find  /  \e(  -newer  ttt  -or  -user wnj  \e)  -print"
733Print out a list of all the files that are either owned by
734.Dq wnj
735or that are newer than
736.Dq ttt .
737.It Li "find  /  \e(  -newer  ttt  -or  -user wnj  \e)  -exit 1"
738Return immediately with a value of 1 if any files are found that are either
739owned by
740.Dq wnj
741or that are newer than
742.Dq ttt ,
743but do not print them.
744.It Li "find  /  \e(  -newer  ttt  -or  -user wnj  \e)  -ls -exit 1"
745Same as above, but list the first file matching the criteria before exiting
746with a value of 1.
747.El
748.Sh SEE ALSO
749.Xr chflags 1 ,
750.Xr chmod 1 ,
751.Xr locate 1 ,
752.Xr xargs 1 ,
753.Xr stat 2 ,
754.Xr fts 3 ,
755.Xr getgrent 3 ,
756.Xr getpwent 3 ,
757.Xr strmode 3 ,
758.Xr symlink 7 ,
759.Xr sysctl 8
760.Sh STANDARDS
761The
762.Nm
763utility syntax is a superset of the syntax specified by the
764.St -p1003.2
765standard.
766.Pp
767The options and the
768.Ic -amin ,
769.Ic -anewer ,
770.Ic -cmin ,
771.Ic -cnewer ,
772.Ic -delete ,
773.Ic -empty ,
774.Ic -execdir ,
775.Ic -follow ,
776.Ic -fstype ,
777.Ic -iname ,
778.Ic -inum ,
779.Ic -iregex ,
780.Ic -links ,
781.Ic -ls ,
782.Ic -maxdepth ,
783.Ic -mindepth ,
784.Ic -mmin ,
785.Ic -path ,
786.Ic -print0 ,
787.Ic -printx ,
788.Ic -regex ,
789and
790.Ic -rm
791primaries are extensions to
792.St -p1003.2 .
793.Pp
794Historically, the
795.Fl d ,
796.Fl h ,
797and
798.Fl x
799options were implemented using the primaries
800.Dq -depth ,
801.Dq -follow ,
802and
803.Dq -xdev .
804These primaries always evaluated to true.
805As they were really global variables that took effect before the traversal
806began, some legal expressions could have unexpected results.
807An example is the expression
808.Dq -print -o -depth .
809As -print always evaluates to true, the standard order of evaluation
810implies that -depth would never be evaluated.
811This is not the case.
812.Pp
813The operator
814.Dq -or
815was implemented as
816.Dq -o ,
817and the operator
818.Dq -and
819was implemented as
820.Dq -a .
821.Pp
822Historic implementations of the
823.Ic -exec
824and
825.Ic -ok
826primaries did not replace the string
827.Dq {}
828in the utility name or the
829utility arguments if it had preceding or following non-whitespace characters.
830This version replaces it no matter where in the utility name or arguments
831it appears.
832.Pp
833Support for
834.Dq Ic -exec Ar ... No +
835is consistent with
836.Em IEEE PASC Interpretation 1003.2 #210 ,
837though the feature originated in
838.Tn SVR4 .
839.Pp
840The
841.Ic -delete
842primary does not interact well with other options that cause the file system
843tree traversal options to be changed.
844.Sh HISTORY
845A much simpler
846.Nm find
847command appeared in First Edition AT\*[Am]T Unix.
848The syntax had become similar to the present version by
849the time of the Fifth Edition.
850.Sh BUGS
851The special characters used by
852.Nm
853are also special characters to many shell programs.
854In particular, the characters
855.Dq \&* ,
856.Dq \&[ ,
857.Dq \&] ,
858.Dq \&? ,
859.Dq \&( ,
860.Dq \&) ,
861.Dq \&! ,
862.Dq \e ,
863and
864.Dq \&;
865may have to be escaped from the shell.
866.Pp
867As there is no delimiter separating options and file names or file
868names and the
869.Ar expression ,
870it is difficult to specify files named
871.Dq -xdev
872or
873.Dq \&! .
874These problems are handled by the
875.Fl f
876option and the
877.Xr getopt 3
878.Dq --
879construct.
880